In the field of current grid-connected photovoltaic power generation technology, multiple direct current power supplies are directly connected in parallel to a direct current bus of an inverter, or the multiple direct current power supplies may be connected to the direct current bus of the inverter through a DC-DC boost circuit.
When an insulation resistance to ground of one of the multiple direct current power supplies is too low, through an insulation resistance detection circuit, the inverter detects that an insulation resistance to ground of the system does not meet safety requirements, and for human safety, the inverter will stop and alarm.
This will cause all direct current power supplies connected in parallel to the direct current bus of the inverter to fail to output normally, which results in power generation loss of the inverter.